This invention relates to a method of and apparatus for assembling articulated claim comprising a plurality of links each including a pair of link sides and a coacting, concentrically disposed pin and bushing means interconnecting the link sides to each other and to another link of the chain and more particularly to such a method and apparatus which is semi-automatic and which does not introduce bending moments into previously assembled portion of the chain.
The severe operating environment of earth moving equipment and particularly crawler type tractors requires maximum quality in components if satisfactory service and life is to be realized. Specifically, the track chains which support, move and steer crawler type tractors and other earth moving equipment encounter some of the highest of loads and wear rates to which components of such equipment are exposed.
Thus, such track chains must be made mechanically strong and heavy. However, they must also be flexible since they provide the means for moving the equipment in operation. Such basic incompatibility in function requires great care in fabrication including careful attention to materials and close tolerances in dimensioning of the parts in order to provide the necessary strength while preserving the equally necessary flexibiliy of the chain.
It has been found that articulated chain made of a plurality of links each consisting of a pair of spaced interconnected link sides joined to each other and to another link by coating, concentrically disposed pin and bushing means will provide the necessary strength and flexibility. The link sides each include a pair of cylindrical apertures dimensioned to received the pins and bushings respectively with a press-fit of very close tolerance. Once assembled such chain is capable of providing long and dependable service in the operation of heavy earth moving equipment.
However, assembly of such chain has presented a number of problems, the most severe of which is the difficulty of aligning and pressing the parts of a link to assemble them with each other and with previously assembled portions of the chain without introducing bending moments in the previously assembled portions of the chain or damage to the parts. Such bending moments are highly undesirable since they will complicate the alignment of the parts of additional links for assembly with each other and with the chain due to the close tolerances and the weight and strength of the materials and parts involved.
It is a primary object of the invention to provide a method and apparatus for assembling track chain of the type described above, a link at a time, without introducing bending moments into the previously assembled portion of the track chain.
It is a further object of this invention to provide a semi-automatic method and apparatus for the assembly of track chain, one link at a time, that avoids the introduction of bending moments into previously assembled portions of the track chain.
It is yet another object of this invention to provide such a method and apparatus which does not require manual steps beyond the capability of one human operator in normal operation.